Effects of silica and zinc oxide doping on mechanical and biological properties of 3D printed tricalcium phosphate tissue engineering scaffolds

Abstract

Objectives To evaluate the effects of SiO2 (0.5 wt %) and ZnO (0.25 wt %) dopants on the mechanical and biological properties of tricalcium phosphate (TCP) scaffolds with three dimensionally (3D) interconnected pores. Methods Scaffolds were created with a commercial 3D printer. Post sintering phase analysis was determined by x-ray diffraction. Surface morphology of the scaffolds was examined by field emission electron microscopy. Mechanical strength was evaluated with a screw driven universal testing machine. MTT assay was used for cellular proliferation characteristics and cellular morphology was examined by field emission electron microscopy. Results Addition of dopants into TCP increased the average density of pure TCP from 90.8 ± 0.8% to 94.1 ± 1.6% and retarded the β to α phase transformation at high sintering temperatures, which resulted in up to 2.5 fold increase in compressive strength. In vitro cell-materials interaction studies, carried out using hFOB cells, confirmed that the addition of SiO2 and ZnO to the scaffolds facilitates faster cell proliferation when compared to pure TCP scaffolds. Significance Addition of SiO2 and ZnO dopants to the TCP scaffolds showed increased mechanical strength as well as increased cellular proliferation.

SrO‐ and MgO‐doped microwave sintered 3D printed tricalcium phosphate scaffolds: Mechanical properties and in vivo osteogenesis in a rabbit model

“…8,[21][22][23] We have recently reported successful direct 3D printing (3DP) of three dimensionally interconnected porous TCP scaffolds with different pore size and volume fraction porosity. 8,23,24 Both pure 8 and doped 23,24 3DP TCP scaffolds showed higher compressive strength compared with scaffolds produced via other solid freeform fabrication (SFF) techniques. 25,26 A significant increase in the mechanical strength of these 3DP interconnected macro porous TCP scaffolds was further achieved by microwave sintering compared with conventional sintering.…”

Biomaterials in Tooth Tissue Engineering: A Review

“…3D CaP porous granules have proved useful in dental tissue engineering by providing favourable 3D substrate conditions for hDPSC growth and odontogenic differentiation [36]. Addition of SiO 2 and ZnO dopants to pure TCP scaffolds increases its mechanical strength as well as cellular proliferation properties [37].…”

Inorganic Polymers: Morphogenic Inorganic Biopolymers for Rapid Prototyping Chain

“…3D printing can also be applied for organic polymers like polylactic acid (PLA), a bioresorbable polymer (Giordano et al 1996). The fabrication of 3D-printed scaffold materials for bone tissue engineering usually requires a sintering process of the initially formed aggregates of the calcium phosphate and bioactive glass granules, preventing an addition of organic growth factors during the scaffold fabrication (Fielding et al 2012). Therefore, the is a strong interest in alternative scaffold materials allowing the fabrication of 3D scaffolds by 3D printing without (post)sintering.…”